KR102311420B1 - Multilayered films, methods of manufacture thereof and articles comprising the same - Google Patents

Abstract

first and second layers; and a multilayer film comprising a tie layer; wherein the tie layer is disposed between the first layer and the second layer; the first layer is disposed on the first surface of the tie layer; the second layer is disposed on the second surface of the tie layer; the second surface is disposed opposite the first surface; The tie layer comprises a crystalline block composite and a carboxylated olefin copolymer.

Description

Multilayered film, method for manufacturing the same, and article comprising the same

The present disclosure relates to multilayered films, methods of making them, and articles comprising the same.

Polypropylene (PP) is often used in the packaging industry in the form of films and containers for packaging of food and non-food products. The PP package offers the advantages of high stiffness, good transparency and high temperature performance. PP or thermoplastic polyolefin (TPO) is frequently used in the automotive industry for panels and components. These polymer panels and components offer the benefits of low weight, flexible styling and lower cost. However, there are limitations such as poor printability/paintability, poor scratch and damage resistance.

first and second layers; and a multilayer film comprising a tie layer; wherein the tie layer is disposed between the first layer and the second layer; the first layer is disposed on the first surface of the tie layer; the second layer is disposed on the second surface of the tie layer; the second surface is disposed opposite the first surface; The tie layer comprises a crystalline block composite and a carboxylated olefin copolymer.

Also a first layer and a second layer; and coextruding the multilayered film comprising a tie layer, wherein the tie layer is disposed between the first layer and the second layer; the first layer is disposed on a first surface of the tie layer; disposed on a second surface of the tie layer; the second surface is disposed opposite the first surface; the tie layer comprising a crystalline block composite and a carboxylated olefin copolymer; and blowing or casting or extrusion coating of the multilayered film.

1 is a schematic representation of a multilayered film.

Terms such as “composition” mean a mixture of two or more substances, such as a polymer blended with other polymers or containing additives, fillers, and the like. Compositions include pre-reaction, reaction, and post-reaction mixtures, the latter comprising reaction products and by-products, as well as unreacted components of the reaction mixture and decomposition products formed from one or more components of the pre-reaction or reaction mixture, if any. will be included

The terms "blend", "polymer blend" and the like refer to a composition of two or more polymers. Such formulations may be miscible or immiscible. Such formulations may or may not be phase separated. Such formulations may or may not contain one or more domain structures as determined by transmission electron microscopy, light scattering, x-ray scattering, and any other method known in the art. The formulation is not a laminate, but one or more layers of the laminate may contain the formulation.

"Polymer" means a compound prepared by polymerization of monomers, whether of the same type or of a different type. The generic term polymer thus encompasses the term homopolymer, which is usually employed to denote a polymer prepared from only one type of monomer, and the term interpolymer, as defined below. It also encompasses all forms of interpolymers, such as random, block, and the like. The terms “ethylene/a-olefin polymer” and “propylene/a-olefin polymer” refer to the interpolymers described below. Polymers are often referred to as "made of" monomers, "substrate" of a specified monomer or monomer type, "containing" a specified monomer content, etc., although this explicitly refers to the polymerized remainder of the specified monomers and is not polymerized. It is noted that it is understood that no reference is made to species.

"Interpolymer" means a polymer prepared by the polymerization of at least two different monomers. The generic term includes copolymers, which are usually employed to refer to polymers prepared from two or more different monomers, and includes polymers prepared from more than two different monomers, such as terpolymers, tetrapolymers, and the like.

The terms "polyolefin", "polyolefin polymer", "polyolefin resin" and the like refer to polymers prepared from simple olefins as monomers (also called alkenes having the _{general formula C n} H _{2n ).} Polyethylene is prepared by ethylene polymerization with or without one or more comonomers, polypropylene is prepared by propylene polymerization with or without one or more comonomers, and so on. Accordingly, polyolefins include interpolymers such as ethylene-α-olefin copolymers, propylene-α-olefin copolymers, and the like.

As used herein, "melting point" (also called melting peak for the shape of the DSC curve shown) is typically determined by the differential scanning calorimetry (DSC) technique for determining the melting point or peak of polyolefins as described in USP 5,783,638. do. Several blends comprising two or more polyolefins will have more than one melting point or peak; It should be noted that several individual polyolefins will contain only one melting point or peak.

The term “and/or” includes both “and” as well as “or”. For example, the terms A and/or B are taken to mean A, B or A and B.

Disclosed herein are multilayered films that can be used in automotive panels and provide the benefits of low weight, flexible styling and lower cost. Multilayered films also exhibit good scratch and damage resistance as well as good printability/paintability that makes them useful in automotive panels. The multilayered film comprises at least three layers, one of which is a crystalline block composite (CBC), a carboxylated ethylene copolymer; and optionally a tie layer comprising a polyolefin based elastomer. The tie layer is used to bond a first layer comprising polypropylene to a second layer (disposed opposite to the first layer) comprising ethylene ionomer, ethylene acrylic acid copolymer, or a combination thereof.

Referring now to FIG. 1 , a multilayer film 100 includes a first layer 102 , a tie layer 104 and a second layer 106 . The tie layer 104 includes a first surface 103 and a second surface 105 disposed opposite to each other. The first layer 102 is in contact with the tie layer 104 at the first surface 103 , while the second layer 106 (disposed opposite to the first layer 102 ) is in contact with the tie layer 104 at the second surface 105 . in contact with layer 104 .

As noted above, the tie layer 104 may include a crystalline block composite (CBC), a carboxylated ethylene copolymer; and optionally polyolefin based elastomers.

The term "crystalline block composite" (CBC) refers to a polymer having three components: a crystalline ethylene based polymer (CEP) (also referred to herein as a soft polymer), a crystalline alpha-olefin based polymer (CAOP) (a hard polymer herein). also referred to as polymer), and a block copolymer comprising a crystalline ethylene block (CEB) and a crystalline alpha-olefin block (CAOB), wherein the CEB of the block copolymer is of the same composition as the CEP in the block composite, The CAOB of the copolymer is the same composition as the CAOP of the block composite. Additionally, the compositional split between the amounts of CEP and CAOP will be essentially the same as the split between the corresponding blocks in the block copolymer. When produced in a continuous process, the crystalline block composite preferably has a polydispersity index (PDI) of 1.7 to 15, specifically 1.8 to 10, specifically 1.8 to 5, more specifically 1.8 to 3.5. Such crystalline block composites are described, for example, in US Patent Application Publication Nos. 2011/0313106, 2011/0313108 and 2011/0313108, all published on December 22, 2011, and herein crystalline block composites, their preparation It is incorporated by reference for a description of the methods and methods of their analysis.

CAOB refers to a highly crystalline block of polymerized alpha olefin units wherein the monomer is present in an amount greater than 90 mol%, specifically greater than 93 mol%, more specifically greater than 95 mol%, specifically greater than 96 mol%. In other words, the comonomer content in the CAOB is less than 10 mol%, specifically less than 7 mol%, more specifically less than 5 mol%, and most specifically less than 4 mol%. CAOBs with propylene crystallinity have a corresponding melting point of at least 80°C, specifically at least 100°C, more specifically at least 115°C, and most specifically at least 120°C. In some embodiments, the CAOB includes all or all propylene units. CEB, on the other hand, is a block of polymerized ethylene units having a comonomer content of 10 mol% or less, specifically 0 mol% to 10 mol%, more specifically 0 mol% to 7 mol%, most specifically 0 mol% to 5 mol% indicates Such CEBs specifically have corresponding melting points of 75°C or higher, more specifically 90°C and 100°C or higher.

In one embodiment, the crystalline block composite polymer comprises propylene, 1-butene or 4-methyl-1-pentene and one or more comonomers. Specifically, the block composite comprises, in polymerized form, propylene and ethylene and/or one or more C _4-20 α-olefin comonomers, and/or one or more additional copolymerizable comonomers, or 4-methyl-1-pentene and ethylene and/or one or more C _4-20 α-olefin comonomers, or 1-butene and ethylene, propylene and/or one or more C ₅ -C ₂₀ α-olefin comonomers and/or one or more additional copolymerizable co-monomers monomers. Additional suitable comonomers are selected from diolefins, cyclic olefins, and cyclic diolefins, vinyl halide compounds, and vinylidene aromatic compounds. Preferably, the monomer is propylene and the comonomer is ethylene.

The comonomer content in the crystalline block composite polymer can be determined using any suitable technique, with techniques based on nuclear magnetic resonance (NMR) spectroscopy being preferred.

The block composite and crystalline block composite have a melting point Tm greater than 100°C, specifically greater than 120°C, and more specifically greater than 125°C. In one embodiment, the Tm is in the range of 100 °C to 250 °C, more specifically in the range of 120 °C to 220 °C, and also specifically in the range of 125 °C to 220 °C. Specifically, the melt flow rate ratio (MFR) of the block composite and the crystalline block composite is 0.1 dg/min to 1000 dg/min, more specifically 0.1 dg/min to 50 dg/min, more specifically 0.1 dg/min to 30 dg /min.

In one embodiment, the block composite and the crystalline block composite are from 10,000 grams/mole (g/mole) to about 2,500,000 g/mole, specifically from 35000 g/mole to about 1,000,000 g/mole, more specifically from 50,000 g/mole and a weight average molecular weight (Mw) of from about 300,000 g/mole to about 300,000 g/mole, specifically from 50,000 g/mole to about 200,000 g/mole.

The crystalline block composite polymer comprises 0.5 wt% to 95 wt% soft copolymer, 0.5 wt% to 95 wt% hard polymer, and 5 wt% to 99 wt% block copolymer. More specifically, the crystalline block composite polymer comprises 0.5 wt% to 79 wt% ductile copolymer, 0.5 wt% to 79 wt% hard polymer and 20 wt% to 99 wt% block copolymer, more specifically 0.5 wt% to 49 wt% wt % soft copolymer, 0.5 wt % to 49 wt % hard polymer, and 50 wt % to 99 wt % block copolymer. Weight percentages are based on the total weight of the crystalline block composite. The sum of the weight percentages of the soft copolymer, hard polymer and block copolymer is 100%.

In one embodiment, the crystalline block composite polymer comprises 0.5 wt% to 95 wt% CEP, 0.5 wt% to 95 wt% CAOP, and 5 wt% to 99 wt% block copolymer. More specifically, the crystalline block composite polymer comprises 0.5 wt% to 79 wt% CEP, 0.5 wt% to 79 wt% CAOP and 20 wt% to 99 wt% block copolymer, more specifically 0.5 wt% to 49 wt% CEP , 0.5 wt% to 49 wt% CAOP and 50 wt% to 99 wt% block copolymer. Weight percentages are based on the total weight of the crystalline block composite. The sum of weight percentages of CEP, CAOP and block copolymer is 100%.

In one embodiment, the block copolymer of the crystalline block composite comprises 5 wt% to 95 wt% crystalline ethylene block (CEB) and 95 wt% to 5 wt% crystalline alpha-olefin block (CAOB). They may comprise from 10 wt % to 90 wt % CEB and from 90 wt % to 10 wt % CAOB. More specifically, the block copolymer comprises 25 wt% to 75 wt% CEB and 75 wt% to 25 wt% CAOB, more specifically 30 wt% to 70 wt% CEB and 70 wt% to 30 wt% CAOB include

In some embodiments, the crystalline block composite has a crystalline block composite index (CBCI) greater than zero, but less than about 0.4, or 0.1 to 0.3. In other embodiments, the CBCI is greater than 0.4, at most 1.0. In some embodiments, the CBCI is from 0.1 to 0.9, from about 0.1 to about 0.8, from about 0.1 to about 0.7, or from about 0.1 to about 0.6. Additionally, the CBCI may range from about 0.4 to about 0.7, from about 0.5 to about 0.7, or from about 0.6 to about 0.9. In some embodiments, the CBCI ranges from about 0.3 to about 0.9, from about 0.3 to about 0.8, or from about 0.3 to about 0.7, from about 0.3 to about 0.6, from about 0.3 to about 0.5, or from about 0.3 to about 0.4. In other embodiments, the CBCI ranges from about 0.4 to about 1.0, from about 0.5 to about 1.0, or from about 0.6 to about 1.0, from about 0.7 to about 1.0, from about 0.8 to about 1.0, or from about 0.9 to about 1.0.

The crystalline block composite may be present in an amount of 40 weight percent (wt%) to 90 wt%, specifically 45 wt% to 85 wt%, more specifically 50 wt% to 75 wt%, based on the total weight of the tie layer 104 . exists as

Carboxylated olefin copolymers include ethylene or propylene polymers grafted with unsaturated carboxylic acids or their anhydrides, esters, amides, imides or metal salts thereof, hereinafter referred to as "grafting compounds". The grafting compound is preferably an aliphatic unsaturated dicarboxylic acid or an anhydride, ester, amide, imide or metal salt derived from such acid. The carboxylic acid preferably contains at most 6, more preferably at most 5 carbon atoms. Alkali metal salts are preferred metal salts. Examples of unsaturated carboxylic acids are maleic acid, fumaric acid, itaconic acid, acrylic acid, methacrylic acid, crotonic acid, and citraconic acid. Examples of unsaturated carboxylic acid derivatives include maleic anhydride, citraconic anhydride, itaconic anhydride, methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, butyl acrylate, butyl methacrylate, glycidyl acrylic Late, glycidyl methacrylate, monoethyl maleate, diethyl maleate, monomethyl fumarate, dimethyl fumarate, monomethyl itaconate, diethyl itaconate, acrylamide, methacrylamide, monomaleamide , dimaleamide, N,N-diethylmaleamide, N-monobutylmaleamide, N,N-dibutylmaleamide, monofumaramide, difumaramide, N-monoethylfumaramide, N,N-di Ethylfumaramide, N-monobutylfumaramide, N,N-dibutylfumaramide, maleimide, N-butylmaleimide, N-phenylmaleimide, sodium acrylate, sodium methacrylate, potassium acrylate, and potassium It is methacrylate. Glycidyl methacrylate is a preferred grafting compound. At least one, preferably one, grafting compound is grafted onto the ethylene or propylene polymer.

The content of grafted compound in the ethylene or propylene polymer is from 0.05 weight percent, more specifically from 0.5 weight percent, most specifically from 2.0 weight percent to 30 weight percent, based on the total weight of the grafted ethylene or propylene polymer; specifically up to 15 weight percent, most specifically up to 8 weight percent.

Decomposition of the initiator to initiate the grafting process by forming free radicals including azo-containing compounds, carboxyl peroxy acids and peroxyesters, alkyl hydroperoxides, and dialkyl and diacyl peroxides, among others. can Several such compounds and their properties have been described (see J. Branderup, E. Immergut, E. Grulke, eds. "Polymer Handbook," 4th ed., Wiley, New York, 1999, Section II, pp. 1). -76.). Alternatively, the grafting compound can be copolymerized with ethylene by conventional tubular and autoclave processes.

The ethylene polymers used for grafting, as well as the grafted ethylene polymers, are ultra-low-density polyethylene (ULDPE), low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), medium-density polyethylene (MDPE), high-density polyethylene (HDPE), high melt strength high density polyethylene (HMS-HDPE), ultra high density polyethylene (UHDPE), or a combination thereof.

In one embodiment, the grafted ethylene or propylene polymer as well as the ethylene or propylene polymer used for grafting is preferably at most 0.902 g/cm3, more preferably from 0.850 g/cm3 to 0.902 g/cm3, most preferably 0.860 g/cm ³ to 0.890 g/cm ³ , in particular 0.865 g/cm ³ to 0.880 g/cm ³ . However, it should be understood that the polymer density changes slightly upon grafting. For ethylene polymers, polymer density has been shown to be important to provide primers with sufficient mechanical strength and flexibility, and to achieve sufficient solubility of the grafted ethylene polymer in organic solvents.

The term "ethylene or propylene polymer" means an ethylene polymer, a propylene polymer, a mixture of different ethylene polymers, a mixture of different propylene polymers or a mixture of at least one ethylene polymer and at least one propylene polymer. Preferred ethylene polymers and propylene polymers are described below. The ethylene or propylene polymer preferably has a crystallinity of from 5 percent to 35 percent, more preferably from 10 percent to 20 percent.

The ethylene or propylene polymer may be an ethylene or propylene homopolymer or an interpolymer of propylene and at least one _{C 4} -C ₂₀ -α-olefin and/or C _{4 -C 18} -diolefin. Preferably, the ethylene polymer is an interpolymer of ethylene and at least one C ₃ -C ₂₀ -α-olefin and/or C ₄ -C ₁₈ -diolefin. Most preferably, the ethylene polymer is an interpolymer of ethylene and _{a C 3} -C ₂₀ -α-olefin having a density of ^{up to 0.902 g/cm 3 .} As used herein, the term “interpolymer” refers to a polymer prepared by the polymerization of at least two different monomers. The generic term interpolymer thus encompasses copolymers, which are usually used to refer to polymers prepared from two different monomers, and polymers prepared from more than two different monomers. Interpolymers may be random or block interpolymers.

Preferred α-olefins contain 4 to 10 carbon atoms, of which 1-butene, 1-hexene, 4-methyl-1-pentene and 1-octene are most preferred. Preferred diolefins are isoprene, butadiene, 1,4-pentadiene, 1,4-hexadiene, 1,5-hexadiene, 1,7-octadiene, 1,9-decadiene, dicyclopentadiene, methylene- norbornene, and 5-ethylidene-2-norbornene. The interpolymer may contain other comonomers, such as C2-C20 acetylenically unsaturated monomers.

Grafted ethylene is a random or block copolymer of ethylene and a C4-C10-α-olefin, most preferably a copolymer of ethylene and 1-butene, 1-hexene, 4-methyl-1-pentene, or 1-octene. may include The ethylene content is preferably greater than 50 percent, more preferably from 60 percent to 90 percent, and most preferably from 70 percent to 80 percent, based on the total weight of the polymer.

Known ethylene polymers can be used for grafting, which preferably have a density within the range mentioned above. One useful type of ethylene polymer is a linear copolymer of ethylene and an a-olefin having a narrow molecular weight distribution, a random distribution of comonomer units along the polymer backbone, and at least 4 carbon atoms having a uniformity index of at least 75. Such polymers are described in US Pat. No. 3,645,992 to Elston. Other useful ethylene polymers and methods of making them are described in US Pat. No. 5,324,800. They have a weight average molecular weight of 500 to 1,400,000 weight average molecular weight, preferably a weight average molecular weight of 1000 to 500,000 and a molecular weight distribution M _w /M _n of 1.5 to 4.0. These are linear copolymers of ethylene and C ₃ -C ₂₀ -α-olefins. Other useful ethylene polymers are described in US Pat. No. 4,429,079. They have a melt index of 0.1 g/10 min to 50 g/10 min, preferably 1 g/10 min to 30 g/10 min, 0.870 g/cm ³ to 0.900 g/cm ³ , preferably 0.875 g/cm ³ a density of to 0.895 g/cm ³ , an X-ray crystallinity of 5 percent to 40 percent, preferably 7 percent to 30 percent, a melting point of 40° C. to 100° C., preferably 60° C. to 90° C., and 85 moles random copolymers of ethylene and α-olefins having 3 to 10 carbon atoms having an ethylene content of percent to 95 mole percent. Ethylene polymers include those polymers available under the trade names TAFMER (trademark of Mitsui Petrochemical) and EXACT (trademark of Exxon Chemical), especially those having a density of ^{up to 0.902 g/cm 3 .}

Most preferred interpolymers of ethylene and at least one C ₃ -C ₂₀ -α-olefin and/or C ₄ -C ₁₈ -diolefin grafted onto the aforementioned grafting compounds are substantially linear ethylene having It is a polymer:

i) from 0.01 to 3 long chain branches per 1000 carbon atoms, depending on the polymer backbone;

ii) melt flow rate ratio, I ₁₀ /I ₂ ≥5.63;

iii) a molecular weight distribution defined by the formula (M _w /M _n )≤(I ₁₀ /I _{2 )-4.63, M w} /M _n , and

^{iv) a critical shear stress greater than 4 x 10 6} dyne/cm ² at the onset of total melt rupture or critical on initiation of surface melt rupture of a linear ethylene polymer having the same melt index and M _w /M _{n at the onset of surface melt rupture} A critical shear rate that is at least 50 percent higher than the shear rate.

Substantially linear ethylene polymers and methods of making them are described in U.S. Pat. Patents 5, 272,236 and 5,278,272 are described in more detail.

Substantially linear ethylene polymers have, depending on the polymer backbone, from 0.01 to, preferably from 0.05 to 3, and preferably from 1 to 1 long chain branches per 1000 carbon atoms. Long chain branches are defined herein as chain lengths of at least about 6 carbon atoms, beyond which lengths are indistinguishable by carbon NMR spectroscopy. Long chain branches can be approximately as long as the polymer backbone. For ethylene/α-olefin copolymers, the long chain branch is at least one carbon longer than the short chain branch that results from the introduction of the a-olefin(s) into the polymer backbone. The experimental effect of the presence of long chain branches in substantially linear ethylene/α-olefin copolymers is manifested in enhanced rheological properties.

Techniques useful for determining the presence of long chain branches in ethylene polymers, including ethylene/1-octene copolymers, are known. Two of these methods are gel permeation chromatography coupled with a low angle laser light scattering detector (GPC-LALLS) and gel permeation chromatography coupled with a differential viscometry detector (GPC-DV). The use of these techniques for long-chain branch detection and intrinsic theory is well reported in the literature. [Zimm, G.H. and Stockmayer, W. H., J. Chem. Phys., 17, 1301 (1949) and Rudin, A., Modern Methods of Polymer Characterization, John Wiley & Sons, New York (1991) pp. 103-112].

In contrast to the term “substantially linear”, the term “linear” means that the polymer has no measurable or identifiable long chain branches, i.e. the polymer is substituted with an average of less than 0.01 long chain branches/1000 carbons.

By “melt index” or “I ₂ ” is meant the melt index as measured according to ASTM D-1238, condition 190° C./2.16 kg. "I ₁₀ " is measured according to ASTM D-1238, Condition 190°C/10 kg. The melt index I ₂ of the substantially linear ethylene polymer is generally from 0.01 g/10 min to 1000 g/10 min, preferably from 0.01 g/10 min to 100 g/10 min. The melt flow rate index ratio, I10/I2, is at least 5.63, preferably at least 6, more preferably at least 7, in contrast to conventional polyethylene, which exhibits a dependence of the melt flow rate index on the polydispersity index and essentially irrelevant.

The polydispersity index (i.e., molecular weight distribution, or ratio of weight average molecular weight to number average molecular weight (Mw/Mn)) of a substantially linear ethylene polymer as determined by gel permeation chromatography is defined by the formula: (Mw /Mn)≤(I10/I2)-4.63. The polydispersity index is preferably less than 3.5, more preferably from 1.5 to 2.5.

Further, a substantially linear ethylene polymer, specifically a substantially linear ethylene polymer, has a critical shear stress of ^{greater than 4 x 10 6} dynes/cm ^{3 at the onset of total melt rupture, as determined by gas extrusion rheometry, or substantially linear} has gas extrusion flowability such that the critical shear rate at the onset of surface melt rupture for the ethylene polymer is at least 50 percent higher than the critical shear rate at the onset of surface melt rupture for the linear ethylene polymer, wherein the substantially linear ethylene polymer and the linear _{The ethylene polymer comprises the same comonomer or comonomers, the linear ethylene polymer having an I 2} , M _w /M _n and density within 10 percent of the corresponding value for a substantially linear ethylene polymer, the substantially linear ethylene polymer The respective critical shear rates of the polymer and the linear ethylene polymer are measured at the same melt temperature using a gas extrusion rheometer.

The determination of the critical shear rate and critical shear stress for melt rupture, as well as other flow properties, is performed using a gas extrusion rheometer (GER). Gas extrusion rheometer [M. Shida, R.N. Shroff and L.V. Cancio in Polymer Engineering Science, Vol. 17, No. 11, p. 770 (1977), and "Rheometers for Molten Plastics" by John Daly, published by Van Nostrand Reinhold Co. (1982) on pp. 97-99].

The substantially linear ethylene polymer has a single differential scanning calorimetry, DSC, melting peak from -30°C to 150°C. A single melting peak may represent a "shoulder" or "hump" on the low-melting side, accounting for less than 12 percent, typically less than 9 percent, and more typically less than 6 percent, of the total heat of fusion of the polymer, depending on equipment sensitivity.

The carboxylated-olefin copolymer is present in an amount of 30 weight percent (wt %) to 60 wt %, specifically 35 wt % to 55 wt %, based on the total weight of the tie layer 104 .

The tie layer 104 may also include an optional elastomer in addition to the crystalline block composite (CBC) and the carboxylated-olefin copolymer. Optional elastomers can be ethylene-α-olefin copolymers (already detailed above), polyolefin elastomers (eg, propylene-based elastomers), vinyl aromatic block copolymers, or the like, or combinations comprising at least one of the foregoing elastomers.

The polyolefin elastomer may also include random or block propylene polymers (ie, polypropylene). Random polypropylene elastomers typically comprise at least 90 mole percent units derived from propylene. The remaining units in the propylene copolymer are derived from at least one α-olefin unit.

The α-olefin component of the propylene copolymer is preferably ethylene (considered α-olefins for the purposes of this invention) or C _4-20 linear, branched or cyclic α-olefins. Examples of C _4-20 α-olefins include 1-butene, 4-methyl-1-pentene, 1-hexene, 1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, and 1-octadecene is included. α-olefins may also contain cyclic structures such as cyclohexane or cyclopentane to give α-olefins such as 3-cyclohexyl-1-propene (allyl cyclohexane) and vinyl cyclohexane. Although not α-olefins in the traditional sense of the term, certain cyclic olefins, such as norbornene and related olefins, in particular 5-ethylidene-2-norbornene, are α-olefins and may be used in place of some or all of the α-olefins described above. can Similarly, styrene and its related olefins (eg, α-methylstyrene, etc.) are α-olefins for purposes of this invention. Exemplary random propylene copolymers include, but are not limited to, propylene/ethylene, propylene/1-butene, propylene/1-hexene, propylene/1-octene, and the like. Exemplary terpolymers include ethylene/propylene/1-octene, ethylene/propylene/1-butene, and ethylene/propylene/diene monomer (EPDM).

In one embodiment, the random polypropylene copolymer has a T _m greater than 120° C., and/or a heat of fusion greater than 70 J/g, both measured by DSC, preferably, but not necessarily, by Ziegler- It is prepared via Natta catalysis.

In another embodiment, the polyolefin elastomer is a propylene-α-olefin interpolymer and is characterized as having a propylene sequence that is substantially isotactic. Propylene-α-olefin interpolymers include propylene-based elastomers (PBE). A “substantially isotactic propylene sequence” means that the sequence is greater than 0.85 as determined by ^{13 C NMR;} greater than 0.90 in the alternative; greater than 0.92 in another alternative; in another alternative means having an isotactic triad (mm) greater than 0.93. Isotactic triads are well known in the art and are described, for example, in USP 5,504,172 and International Publication No. WO 00/01745, which show isotactic sequences in terms of triad units of copolymer molecular chains as determined by ^{13 C NMR spectra.} described.

The propylene-α-olefin copolymer comprises units derived from propylene and polymerized units derived from one or more α-olefin comonomers. Exemplary comonomers used to prepare the propylene-α-olefin copolymer include C2 and C4 to C10 α-olefins; For example, C2, C4, C6 and C8 α-olefins.

The propylene-α-olefin interpolymer comprises from 1 weight percent to 40 weight percent of one or more alpha-olefin comonomers. All individual values and subranges from 1 weight percent to 40 weight percent are included herein and disclosed herein. The propylene-α-olefin interpolymer may have a melt flow rate ranging from 0.1 grams/10 minutes (g/10 minutes) to 500 g/10 minutes as measured according to ASTM D-1238 (at 230° C./2.16 Kg). The propylene-α-olefin interpolymer has a crystallinity ranging from at least 1 weight percent (heat of fusion (H _f ) of at least 2 Joules/gram (J/g)) to 30 weight percent (H _{f less than 50 J/g).} have The propylene-α-olefin interpolymers typically have a density of less than ^{0.895 g/cm 3 .} The propylene-α-olefin interpolymer has a melting temperature (T _m ) of less than 120° C. and a heat of fusion (H ) of less than 70 Joules/gram (J/g) as determined by differential scanning calorimetry (DSC) described in USP 7,199,203. _f ). propylene-α-olefin interpolymer is 3.5 or less; or 3.0 or less; or a molecular weight distribution (MWD) defined as the weight average molecular weight (Mw/Mn) divided by the number average molecular weight of 1.8 to 3.0.

Such propylene-α-olefin interpolymers are further described in USPs 6,960,635 and 6,525,157, the entire contents of which are incorporated herein by reference. Such propylene-α-olefin interpolymers are commercially available from The Dow Chemical Company under the tradename VERSIFY™, or from ExxonMobil Chemical Company under the tradename VISTAMAXX™.

The term vinyl aromatic block copolymer refers to a polymer having at least one block segment of a vinyl aromatic monomer in combination with at least one saturated or unsaturated elastomeric monomer segment, and more preferably having no polymer blocks that are neither elastomeric nor vinyl aromatic. it means. An example of a vinyl aromatic block copolymer is "styrenic block copolymer or styrenic block copolymer". The term "styrenic block copolymer" or "styrenic block copolymer" has at least one block segment of a styrenic monomer in combination with at least one saturated or unsaturated elastomeric (rubber) monomer segment, more preferably a rubber degree or a polymer that does not have a polymer block that is not even styrenic. Suitable styrene block copolymers having unsaturated rubber monomer units include styrene-butadiene (SB), styrene-isoprene (SI), styrene-butadiene-styrene (SBS), styrene-isoprene-styrene (SIS), α-methylstyrene-butadiene -α-methylstyrene, α-methylstyrene-isoprene-α-methylstyrene, and the like are included.

The term “styrene butadiene block copolymer” is used herein to include SB, SBS, and a greater number of styrene (S) and butadiene (B) blocks. Similarly, the term "styrene isoprene block copolymer" is used to encompass polymers having at least one block of styrene and one isoprene (I). The structure of the styrenic block copolymer may be of a linear or radial type, and may be of a two block, three block or more block type. In some embodiments, styrenic block copolymers having at least four different blocks or a pair of two repeating blocks, such as repeating styrene/butadiene or styrene/ethylene propylene blocks, are preferred. Styrene block copolymers are commercially available from Dexco Polymers under the trade names VECTOR®, from KRATON Polymers under the trade names KRATON™, from Chevron Phillips Chemical Co. under the trade names SOLPRENE™ and K-Resin, and from BASF Corp. under the trade names Styrolux™. . The styrenic block copolymers are optionally used alone or in combination of two or more.

The styrenic portion of the block copolymer is preferably a polymer or interpolymer of styrene or α-methylstyrene and its analogues or homologues, including ring-substituted styrenes, especially ring-methylated styrenes. Preferred styrenic systems are styrene and ?-methylstyrene, with styrene being particularly preferred.

The elastomeric portion of the styrenic block copolymer is optionally unsaturated or saturated. Block copolymers having unsaturated elastomeric monomer units may include homopolymers of butadiene or isoprene and copolymers of one or both of these two dienes together with small amounts of styrenic monomers. When the monomer employed is butadiene, it is preferred that from about 35 mole percent to about 55 mole percent of the condensed butadiene units in the butadiene polymer block have a 1,2-structure. When these blocks are hydrogenated, the resulting product is or mimics canonical copolymer blocks of ethylene and 1-butene (EB). When the conjugated diene employed is isoprene, the resulting hydrogenated product is or mimics a canonical copolymer block of ethylene and propylene (EP). Preferred block copolymers more preferably have unsaturated elastomeric monomer units comprising at least one segment of styrenic units and at least one segment of butadiene or isoprene, with SBS and SIS being most preferred. Of these, SIS is preferred, as it has been shown to be particularly effective for compatibilizing polypropylene with other polymers in the composition. It is also preferred because it has a lower tendency to cross-link and form a gel during manufacture compared to SBS. Styrene butadiene block copolymers are alternatively preferred when a cast tenter line is used in film production where higher transparency and lower haze are advantageous.

The elastomeric styrenic block copolymer provides the toughness and lower stiffness that would be obtained in the absence of the block copolymer. The elastomeric behavior is advantageously at least about 200 percent, specifically at least about 220 percent, more specifically at least about 240 percent, most specifically at least about 260 percent and specifically at least about 200 percent, as measured by ASTM D412 and/or ASTM D882 procedures. It exhibits a percent tensile elongation at break characteristic of up to about 2000 percent, more specifically up to about 1700 percent, and most specifically up to about 1500 percent. Industrially, most polymers of this type contain from 10 wt % to 80 wt % styrene. Within certain types and types of polymers, the elastomeric properties of the block copolymer decrease as the styrene content increases.

The block copolymer preferably has a melt flow rate of at least about 2 grams/10 min (g/10 min), specifically at least about 4 g/10 min, specifically 20 g/10 min, more specifically 30 g/10 min. (MFR). MFR is measured according to ASTM Method D1238 Condition G.

Preferred styrenic block copolymers include styrene-isoprene-styrene block copolymers (“SIS”), styrene-butadiene-styrene block copolymers (“SBS”), styrene-ethylene-propylene block copolymers (“SEP”), and hydrogenated styrenic block copolymers such as styrene-(ethylene butylene)-styrene block copolymers (“SEBS”) (eg, SEBS commercially available from Kraton Polymers LLC under the trade designation Kraton™ 1657). Preferably, the styrenic block copolymer used in the tie layer is SBS.

In one embodiment, the styrene butadiene block copolymer has a radial or star block structure with polybutadiene at the core and polystyrene at the ends of the arms. Such polymers are referred to herein as star styrene butadiene block copolymers, are within the skill of one of ordinary skill in the art, and are commercially available from Chevron Phillips Chemical Co. under the trade name K-Resin. These polymers contain at least about 27% butadiene in star-block form and are often characterized by the bimodal molecular weight distribution of polystyrene. The inner polybutadiene segments have approximately the same molecular weight, while the outer polystyrene segments have different molecular weights. This feature facilitates control of the polybutadiene fragment thickness to obtain improved transparency. For high transparency, the polybutadiene fragment thickness is preferably about 1/10 or less of the wavelength of the visible spectrum.

Ethylene-α-olefin copolymers have been described above with polyethylene and will not be described again. Polypropylene will be described for layer 102 below.

If an elastomer is used, it is present in an amount of up to 50 wt %, specifically 10 wt % to 30 wt %, based on the total weight of the tie layer 104 . The tie-layers 104 each have a thickness of 1% to 20%, specifically 2% to 10%, specifically 3% to 8%, and more specifically 4% to 6% of the total thickness of the multilayer film.

The first layer 102 comprises polypropylene. It may also optionally include polyethylene in addition to the elastomer and propylene. Polypropylene is random copolymer polypropylene (rcPP), impact copolymer polypropylene (hPP + at least one elastomeric impact modifier) (ICPP) or high impact polypropylene (HIPP), high melt strength polypropylene (HMS-PP) , isotactic polypropylene (iPP), syndiotactic polypropylene (sPP), or combinations comprising at least one of said polypropylenes.

Polypropylene is generally a homopolymer polypropylene in isotactic form, although other forms of polypropylene may also be used (eg, syndiotactic or atactic). However, polypropylene impact copolymers (e.g., those employing a secondary copolymerization step of reacting ethylene with propylene) and random copolymers (also reactively modified and usually containing 1.5% to 7% ethylene copolymerized with propylene) are also described herein. It can be used in the TPO formulation disclosed in A full discussion of the various polypropylene polymers can be found in Modern Plastics Encyclopedia/89, mid October 1988 Issue, Volume 65, Number 11, pp. 86-92, the entire disclosure of which is incorporated herein by reference. The molecular weight of the polypropylene for use in the present invention, and hence the melt flow rate, varies with the application. Melt flow rates for polypropylenes useful herein are generally from about 0.1 grams/10 min (g/10 min, measured at 230°C and 2.16 kg according to ASTM D1238) to about 100 g/10 min, specifically 0.5 g/min. from 10 min to about 80 g/10 min, specifically from 4 g/10 min to about 70 g/10 min. The propylene polymer may be a polypropylene homopolymer, or it may be a random copolymer or even an impact copolymer (which already contains a rubbery phase). Examples of such propylene polymers include VISTAMAX (manufactured by Exxon Mobil), VERSIFY and INSPIRE (manufactured by The Dow Chemical Co.), and PROFAX (manufactured by Lyondell).

The first layer 102 may contain polypropylene in an amount of 40 wt % to 100 wt %, specifically 50 wt % to 90 wt %, based on the total weight of the first layer 102 .

The first layer 102 may optionally contain elastomer in an amount of up to 40 wt %, specifically 10 wt % to 35 wt %, based on the total weight of the first layer. The elastomer can be an ethylene-α-olefin copolymer (already described above), a polyolefin elastomer (eg, a propylene-based elastomer), a vinyl aromatic block copolymer, or a combination thereof, as described above. The first layer may also contain polyethylene in an amount of up to 40 wt %, specifically 10 wt % to 35 wt %, based on the total weight of the first layer. Polyethylene has been described above and will not be described again herein.

The first layer 102 has a thickness of 30% to 80%, specifically 40% to 70%, more specifically 50% to 70%, based on the total thickness of the multilayered film 100 . In one exemplary embodiment, the first layer has a thickness that is at least 50% of the total thickness of the multilayered film.

The second layer 106 comprises an ethylene ionomer or an ethylene acrylic acid copolymer or a combination thereof.

The acrylic acid ethylene copolymer contains 5 wt% to 50 wt%, specifically 10 wt% to 20 wt%, of a polar monomer, such as acrylic acid, alkyl acrylic acid, or alkyl acrylate, or a combination thereof, based on the total weight of the ethylene copolymer. , more specifically a polymer that may include repeat units in an amount of 12 wt % to 15 wt %. Alkyl groups may contain from 1 to 20 carbon atoms. The remainder of the copolymer is an ethylene polymer. Ethylene polymers, including ethylene-α-olefin copolymers (described above), may be employed in acrylic acid ethylene copolymers or ethylene ionomers (described below).

Examples of such polar monomers include acrylic acid, methacrylic acid, ethacrylic acid, methyl acrylate, ethyl acrylate, methyl methacrylate, ethyl methacrylate, propyl acrylate, propyl methacrylate, isopropyl acrylate, isopropyl Methacrylate, butyl acrylate, butyl methacrylate, isobutyl acrylate, isobutyl methacrylate, tert-butyl acrylate, tert-butyl methacrylate, octyl acrylate, octyl methacrylate, undecyl acrylate , undecyl methacrylate, octadecyl acrylate, octadecyl methacrylate, dodecyl acrylate, dodecyl methacrylate, 2-ethylhexyl acrylate, 2-ethylhexyl methacrylate, isobornyl acrylate, iso Bornyl methacrylate, lauryl acrylate, lauryl methacrylate, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, glycidyl acrylate, glycidyl methacrylate, poly(ethylene glycol) )acrylate, poly(ethylene glycol) methacrylate, poly(ethylene glycol) methyl ether acrylate, poly(ethylene glycol) methyl ether methacrylate, poly(ethylene glycol) behenyl ether acrylate, poly(ethylene glycol) behenyl ether methacrylate, poly(ethylene glycol) 4-nonylphenyl ether acrylate, poly(ethylene glycol) 4-nonylphenyl ether methacrylate, poly(ethylene glycol) phenyl ether acrylate, poly(ethylene glycol) phenyl ether methacrylate, dimethyl maleate, diethyl maleate, dibutyl maleate, dimethyl fumarate, diethyl fumarate, dibutyl fumarate, dimethyl fumarate, vinyl acetic acid, vinyl acetate, vinyl propionate, or these combinations of are included.

The ethylene copolymer may contain up to 35 wt % of optional comonomers such as carbon monoxide, sulfur dioxide, acrylonitrile; Maleic anhydride, maleic diester, (meth)acrylic acid, maleic acid, maleic acid monoester, itaconic acid, fumaric acid, fumaric acid monoester, salts of these acids, glycidyl acrylate, glycidyl methacrylate, and glycidyl vinyl ether, or a combination thereof.

In one embodiment, the acid moiety of the ethylene copolymer can be neutralized with a cation to produce an ionomer. Neutralization is, for example, from 0.1 wt% to 100 wt%, specifically from 10 wt% to 90 wt%, specifically from 20 wt% to 80 wt%, more specifically from 20 wt%, with metallic ions, based on the total carboxylic acid content. % to about 40 wt%. The metallic ion may be monovalent, divalent, trivalent, polyvalent, or a combination of two or more thereof. Examples include Li, Na, K, Ag, Hg, Cu, Be, Mg, Ca, Sr, Ba, Cd, Sn, Pb, Fe, Co, Zn, Ni, Al, Sc, Hf, Ti, Zr, Ce, or combinations thereof. When the metallic ion is polyvalent, complexing agents such as stearate, oleate, salicylate and phenolate radicals may be included.

The ionomer may also be a blend of an ionomer having greater than 20% neutralization and, for example, an ethylene(meth)acrylic acid copolymer to achieve the desired degree of neutralization.

Examples of ethylene copolymers include ethylene/methyl acrylate (EMA), ethylene/ethyl acrylate (EEA), ethyl acrylate (EA), ethylene/butyl acrylate (EBA), ethylene/isobutyl acrylate/methacrylic acid , ethylene/methyl acrylate/maleic anhydride, ethylene/butyl acrylate/glycidyl methacrylate (EBAGMA) and ethylene/butyl acrylate/carbon monoxide (EBACO), and butylacrylate (BA). Examples of commercially available ethylene copolymers include those available from EI du Pont de Nemours and Company (DuPont), Wilmington, Del. carrying the trade names Surlyn®, Nucrel®, Appeel®, Bynel®, Elvaloy®, and Elvax®. things are included

The second layer 106 may also include a metal foil comprising aluminum, copper, tin or gold. When the second layer comprises a metal, the preferred metal is aluminum foil.

The second layer 106 has a thickness of 5% to 80%, specifically 7% to 70%, more specifically 10% to 60%, based on the total thickness of the multilayered film 100 . In an exemplary embodiment, the first layer has a thickness that is at least 50% of the total thickness of the multilayered film.

Each layer of the multilayer film 100 may contain other additives, such as waxes, antioxidants, anti-ozone agents, mold release agents, biocides, heat stabilizers, pigments, dyes, infrared absorbers, ultraviolet stabilizers, etc., or at least one of the above combinations comprising additives.

One or more layers of the multilayer film may optionally include a wax capable of reducing melt viscosity in addition to reducing cost. Non-limiting examples of suitable waxes include petroleum waxes, polyolefin waxes such as low molecular weight polyethylene or polypropylene, synthetic waxes, paraffin and microcrystalline waxes having a melting point of from about 55°C to about 110°C, Fischer-Tropsch waxes, or at least one combinations comprising the wax of In some embodiments, the wax is a low molecular weight polyethylene homopolymer or interpolymer having a number average molecular weight of from about 400 g/mole to about 6,000 g/mole.

In a further embodiment, each layer of the multilayer film may optionally include an antioxidant or stabilizer. Non-limiting examples of suitable antioxidants include amine-based antioxidants such as alkyl diphenylamines, phenyl-α-naphthylamines, alkyl or aralkyl substituted phenyl-α-naphthylamines, alkylated p-phenylene diamines, tetramethyl-diaminodiphenylamine and the like; and hindered phenolic compounds such as 2,6-di-t-butyl-4-methylphenol; 1,3,5-trimethyl-2,4,6-tris(3′,5′-di-t-butyl-4′-hydroxybenzyl)benzene; tetrakis[(methylene(3,5-di-t-butyl-4-hydroxyhydrocinnamate)]methane (eg, IRGANOX™ 1010, Ciba Geigy, New York); octadecyl-3,5-di-t -Butyl-4-hydroxycinnamate (e.g., IRGANOX™ 1076, commercially available from Ciba Geigy) and combinations thereof.When used, the amount of antioxidant in the composition depends on the total weight of any particular layer. It may be up to about 1 wt %, specifically 0.05 wt % to 0.75 wt %, specifically 0.1 wt % to 0.5 wt %.

In a further embodiment, the compositions disclosed herein may optionally include a UV stabilizer capable of preventing or reducing degradation of the composition by UV radiation. Non-limiting examples of suitable UV stabilizers include benzophenones, benzotriazoles, aryl esters, oxanilides, acrylic acid esters, formamidine carbon black, hindered amines, nickel quenchers, hindered amines, phenolic antioxidants, metallic salts. , zinc compounds, etc., or combinations comprising at least one of the above UV stabilizers. When employed, the amount of UV stabilizer in any particular layer may be greater than about 0 wt % to about 1 wt %, specifically 0.05 wt % to 0.75 wt %, specifically 0.1 wt %, based on the total weight of any particular layer. to 0.5 wt%.

In further embodiments, the compositions disclosed herein may optionally include a colorant or pigment. Any dye or pigment known to one of ordinary skill in the art may be used in the adhesive compositions disclosed herein. Non-limiting examples of suitable dyes or pigments include inorganic pigments such as titanium dioxide and carbon black, phthalocyanine pigments, and other organic pigments such as IRGAZIN®, CROMOPHTAL®, MONASTRAL®, CINQUASIA®, all available from Ciba Specialty Chemicals, Tarrytown, NY. , IRGALITE®, ORASOL®. When employed, the amount of dye or pigment in any particular layer can be up to 10 wt%, specifically 0.1 wt% to 5 wt%, more specifically 0.5 wt% to based on the total weight of any particular layer of the multilayered film. It may be present in an amount of 2 wt %.

In one embodiment, in one method of making the film 100 , each composition for each of the layers 102 , 104 , and 106 of the multilayered film 100 is subjected to shear, extension, and elongation forces. Supplied as a separate device. The device for applying the force onto the composition may be an extruder (single or twin screw), a Henschel mixer, a Waring blender, a Buss smelter, a Banbury, a roll mill (two or more rolls), a high shear impeller disperser, a dough mixer, and the like. The components for any layer of the multilayered film may be dry mixed or solution blended in a Henschel mixer, Waring blender, high shear impeller disperser, etc. prior to extrusion.

In one exemplary embodiment, the composition for each of each layer is fed to a separate extruder. The composition for the first layer 102 is fed to a first extruder, the composition for the tie layer 104 is fed to a second extruder, and the composition for the third layer 106 is fed to a third extruder. The composition from each extruder is fed into a single die and co-extruded to form a multilayered film. The coextruded film is then blown to form a multilayered film of the desired thickness. In one embodiment, the multilayered film after being coextruded is laminated in a roll mill having two or more rolls.

In another embodiment, in another method of making a multilayered film, each layer can be extruded separately, and then the extruded layers can be formed into a laminate (eg, extrusion lamination, thermal lamination, compression molding, adhesive lamination). ). Compression molding or lamination may be performed in a roll mill or compression molding press.

In another embodiment, in another method of making a multilayered film, two layers can be coextruded together, and then the coextruded layers can be coated with or laminated with a third layer. Extrusion coating involves extrusion of resin from a slot die onto a moving web, which can then be passed through a nip consisting of rubber covered pressure rollers and chrome plated cooling rolls. The latter cools the molten film back to a solid state and also imparts the desired finish to the plastic surface. For example, the second layer 106 may be aluminum foil, and layers 102 and 104 may be coated onto the aluminum foil via an extrusion coating process.

As described above, a plurality of multilayered films may be laminated together to form one multilayered film. When two or more multilayered films are laminated together, at least one common layer may be omitted if necessary. For example, when two multilayered films are laminated together, at least one second layer 106 may be omitted. Thus one multilayered film will contain 3 layers, but two multilayered films laminated together will contain 5 layers and 3 multilayered films will contain 7 layers.

The multilayered film disclosed herein exhibits improved stiffness, strong heat sealing strength without delamination, high creep resistance, high temperature performance and oil/wrinkle resistance, and excellent optical transparency, due to the presence of a core layer comprising polypropylene in the multilayered film. It is advantageous in that it allows the multilayered film to be used in packaging, automotive panels, and the like. Depending on their intended use, the multilayer film or sheet structure according to the present invention can be designed to meet specific performance requirements.

The multilayered films and methods of making the films disclosed herein are illustrated in the Examples below.

Example

Example 1

This example shows the disclosed multilayered films and methods of making them. These examples were also performed to show the properties of the multilayered films compared to the multilayered control films. The evaluations performed on the film are detailed below.

The components used in the various layers of the multilayered film (for this and subsequent examples) are detailed in Table 1 below.

matter Explanation CBC1 50/50 EP/iPP, 90wt% C2 in EP, 6.0 MFR Lotader 8840 Glycidyl (GMA) methacrylate-ethylene copolymer, 5 MI, 8% GMA, Arkema PRIMACOR 3440 Ethylene Acrylate Copolymer, 10 MI, 9.7% AA, Dow Chemical PRIMACOR 3150 Ethylene Acrylate Copolymer, 11 MI, 3% AA, Dow Chemical AFFINITY PL1850 ELVAX 265 Ethylene Acetate Ethylene Copolymer, 3MI, 28% VA, DuPont PP D221 Homo PP, 35 MFR, Dow Chemical AMPLIFY 3801 Ethylene ionomer, Na form, 1.3 MI, acrylic acid content before neutralization is 8.8% Irganox B225 antioxidant

The crystalline block composite (CBC1) has the properties shown in Table 1A below.

[Table 1A]

The formulations of the ingredients in Table 1, impact modifiers and compatibilizers were performed on a Haake Rheomix 3000 rotating at 50 revolutions per minute (RPM). Preheat the mixer to 190°C and hold the mix for 5 minutes after the ram is safely dropped. The formulation is as shown in Table 2. Control film samples are indicated by letters (see Samples A-E), while samples exemplifying the present invention are indicated by numbers (see Samples 1 - 2). The layer structures for control samples A-E and inventive samples 1-2 are shown in Table 2. The preparation method of the sample is shown in detail below, and the properties of the control sample and the sample of the present invention are shown in Table 3.

Sample # CBC1 (wt%) Lotader 8840 (wt%) PRIMACOR 3440 (wt%) PRIMACOR 3150 (wt%) Irganox B225 (wt%) A 76.8 20 0.2 One 61.8 35 0.2 2 46.8 50 0.2 B 76.8 20 0.2 C 61.8 35 0.2 D 48.8 50 0.2 E 61.8 35 0.2

The face-to-face bonded sections used for the T-peel adhesion evaluation were prepared by lamination, ie, melt bonding, of two compression molded sections of an attachment pair. Extrusion sections for melt bonding are 1 mm thick from which peel specimens will be die cut and separated for evaluation. It is desirable that all peel specimens fail at the bonding zone so that actual adhesion can be measured. It is also desirable for the adhesive force to have a minimal contribution from the bending force applied to the specimen. Therefore, the 1-mm thickness was chosen to balance the trade-off between minimizing tearing in the layer (eg maximizing thickness) and minimizing bending forces on the layer (minimizing thickness) during delamination evaluation.

Sample preparation is detailed as follows:

Step 1: Compression molding of individual sections at 190° C. under 25000 pounds per square inch (psi) pressure for 5 minutes.

Step 2: Lay and reshape the pair at 190°C under 200 psi contact pressure for 10 minutes

Step 3: The bonded sections were conditioned in an ASTM environment for 48 hours prior to delamination evaluation. The combined sections were cut into 25 mm X 250 mm strips with about 75 mm long legs by a NAEF punch press.

T-Peel Assessment:

The evaluation method used is a 180° peel strength measurement on a partially pre-peeled film using a constant stretching rate of 254 mm/min. All measurements were performed in a temperature controlled room at 23°C. The strip was held and peeled by an INSTRON Model 1122 manufactured by INSTRU-MET Corporation. The INSTRON is actuated by pneumatic grips, separating the two specimen legs by 180°, leaving a joined area at 90° on each leg, starting with an initial distance of approximately 50 mm between the two grips and a constant separation rate of 254 mm/min. was used. Each specimen was pulled to 75 mm. Tensile-stress curves were recorded for 5 independent specimens per pair. The average peak load is reported and averaged as the average adhesive strength between the markers at the start of peeling and at the end of the peak load.

Table 3 shows the adhesion grades.

Adhesion Value (lbf/in) ranking no peeling excellent >5 excellent 1-5 suitable <1 bad

Adhesion to different substrates including PP D221m ionomer 3801, PRIMACOR 3440 and aluminum foil is summarized in Table 4. The inventive examples (Samples #1 and 2) show excellent adhesion to PP and ionomer 3801. Additionally, sample #1 shows good adhesion to PRIMACOR 3440, while sample #2 shows excellent adhesion to PRIMACOR 3440 and good adhesion to aluminum foil. On the other hand, the controls, i.e. samples #A-H, show sufficient adhesion to either PP or ionomer 3801 but not to both.

Sample # CBC1 (wt%) Lotader 8840 P-3440 P- 3150 B225 write PP D221 Ionomer 3801 P-3440 aluminum foil A 76.8 20 0.2 E ^* P ^* P P One 61.8 35 0.2 E E G P 2 46.8 50 0.2 E E E G B 76.8 20 0.2 E P P P C 61.8 35 0.2 E P G P D 48.8 50 0.2 P E E G E 61.8 35 0.2 E P P P F CBC1 E P P P G PL1850 P F ^* G ^* P H ELVAX 265 P F G E

^* E=excellent; P=poor, G=excellent; F = Moderate

Claims (16)

A multilayer film comprising:
a first layer comprising polypropylene and a second layer comprising ethylene ionomer, ethylene acrylic acid copolymer or a combination thereof or metal foil; and
a tie layer;
the tie layer is disposed between the first layer and the second layer; the first layer is disposed on a first surface of the tie layer; the second layer is disposed on a second surface of the tie layer; the second surface is disposed opposite the first surface; wherein the tie layer comprises a crystalline block composite and a carboxylated olefin copolymer, wherein the carboxylated olefin copolymer is present in an amount from 30 wt % to 60 wt %. The multilayer film of claim 1 , wherein the carboxylated olefin copolymer is a carboxylated ethylene copolymer or a carboxylated propylene copolymer. The multilayer film of claim 1 , wherein the carboxylated olefin copolymer is a glycidyl methacrylate ethylene copolymer. The multilayer film of claim 1 , wherein the carboxylated olefin copolymer comprises a grafting compound in an amount of 0.05 wt % to 30 wt %, based on the total weight of the carboxylated olefin copolymer. The method of claim 1 , wherein: the tie layer further comprises an elastomer; and wherein the elastomer is a homogeneously branched ethylene-α-olefin copolymer, a polyolefin elastomer, a vinyl aromatic block copolymer, or a combination comprising at least one of the elastomers. The multilayer film of claim 1 , wherein the crystalline block composite has a melt flow rate ratio of 0.1 dg/min to 30 dg/min, as measured according to ASTM D 1238 at 230° C. and 2.16 kg. The multilayer film of claim 1 , wherein the crystalline block composite comprises 5 wt% to 95 wt% crystalline ethylene blocks and 5 wt% to 95 wt% crystalline alpha-olefin blocks. The method of claim 1 , wherein: the first layer comprises polypropylene; and wherein said polypropylene comprises at least one of random copolymer polypropylene, impact copolymer polypropylene, high impact polypropylene, high melt strength polypropylene, isotactic polypropylene, syndiotactic polypropylene, or said polypropylene Selected from the group consisting of, a multilayer film. The method of claim 1 , wherein the second layer comprises an ethylene ionomer, an ethylene acrylate copolymer, or a combination thereof, and wherein the tie layer consists of a crystalline block composite, a carboxylated olefin copolymer, and optionally an elastomer; wherein the elastomer is a homogeneously branched ethylene-α-olefin copolymer, a polyolefin elastomer, a vinyl aromatic block copolymer, or a combination comprising at least one of the elastomers. 10. The method of claim 9, wherein the acrylic acid ethylene copolymer is acrylic acid, methacrylic acid, ethacrylic acid, methyl acrylate, ethyl acrylate, methyl methacrylate, ethyl methacrylate, propyl acrylate, propyl methacrylate, isopropyl Acrylate, isopropyl methacrylate, butyl acrylate, butyl methacrylate, isobutyl acrylate, isobutyl methacrylate, tert-butyl acrylate, tert-butyl methacrylate, octyl acrylate, octyl methacrylate , undecyl acrylate, undecyl methacrylate, octadecyl acrylate, octadecyl methacrylate, dodecyl acrylate, dodecyl methacrylate, 2-ethylhexyl acrylate, 2-ethylhexyl methacrylate, iso Bornyl acrylate, isobornyl methacrylate, lauryl acrylate, lauryl methacrylate, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, glycidyl acrylate, glycidyl methacrylate , poly(ethylene glycol) acrylate, poly(ethylene glycol) methacrylate, poly(ethylene glycol) methyl ether acrylate, poly(ethylene glycol) methyl ether methacrylate, poly(ethylene glycol) behenyl ether acrylate, Poly(ethylene glycol) behenyl ether methacrylate, poly(ethylene glycol) 4-nonylphenyl ether acrylate, poly(ethylene glycol) 4-nonylphenyl ether methacrylate, poly(ethylene glycol) phenyl ether acrylate, poly (ethylene glycol) phenyl ether methacrylate, dimethyl maleate, diethyl maleate, dibutyl maleate, dimethyl fumarate, diethyl fumarate, dibutyl fumarate, dimethyl fumarate, vinyl acetic acid, vinyl acetate, vinyl propane A multilayer film derived from the polymerization of an ethylene polymer with a cionate, or a combination thereof. 11. The method of claim 10, wherein the ethylene acrylate copolymer is neutralized with ions, and wherein the ions are Li, Na, K, Ag, Hg, Cu, Be, Mg, Ca, Sr, Ba, Cd, Sn, Pb, Fe, A multilayer film comprising Co, Zn, Ni, Al, Sc, Hf, Ti, Zr, Ce, or combinations thereof. The method of claim 1 , wherein: the second layer comprises a metal foil; wherein the metal foil comprises aluminum, copper, gold or tin. An article comprising the multilayer film of claim 1 . A method for producing a multilayer film, comprising:
A first layer comprising polypropylene and a second layer comprising an ethylene ionomer, an ethylene acrylic acid copolymer, or a combination thereof, and
co-extruding a film comprising a tie layer; and
blowing or casting or extrusion coating the coextruded film;
the tie layer is disposed between the first layer and the second layer, the first layer is disposed on a first surface of the tie layer, and the second layer is disposed on a second surface of the tie layer. wherein said second surface is disposed opposite said first surface, said tie layer comprising a crystalline block composite and a carboxylated olefin copolymer, wherein said carboxylated olefin copolymer comprises from 30 wt % to 60 wt % A method of making a multilayer film, which is present in an amount. 15. The method of claim 14,
and laminating the film with a roll mill. 15. The method of claim 14,
and laminating the film to an extrusion mold.

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